Fragmentation production of J ψ and ψ′ at the Tevatron

We present a calculation of the charm and gluon fragmentation contributions to inclusive J ψ and ψ′ production at large transverse momentum at the Tevatron. For ψ production, we include both fragmentation directly into ψ and fragmentation into χ_c followed by the radiative decay χ_c → ψ + λ. We find that fragmentation overwhelms the leading-order mechanisms for prompt ψ production at large p_T, and that the dominant contributions come from fragmentation into χ_c. Our results are consistent with recent data on ψ production from the CDF and D0 experiments. In the case of prompt ψ′ production, the dominant mechanism at large p_T is charm fragmentation into ψ′. We find serious disagreement between our theoretical predictions and recent ψ′ data from the Tevatron.